A structured light is a light with a specified pattern. With increasing development of optical technologies, the structured light is designed to have a linear pattern, a planar pattern, a grid pattern or even a complicated light pattern. Consequently, the structured light can be applied to many fields such as 3D contour regeneration technologies, distance measurement technologies, anti-counterfeiting recognition technologies, motion sensitive technologies, novel appearance designs and associated applications. For example, by using the structured light, the conventional warning signs can be extensively applied to medical applications or biomedical applications that require pollution-free environments. In other words, the importance of the structured light is progressively increased and the associated technologies are widely explored.
Generally, a structured light generation unit is used for generating a structured light. There are basically two types of structured light generation units, i.e., with or without moving part. The moving part, e.g., by a MEMS or by a rotator which is a mechanical mechanism, could change light pattern. When the structured light is projected on an object, a structured light pattern is formed on a surface of the object. The structured light pattern on the surface of the object is an important identification feature for judging the spatial information. However, regardless of whether the structured light pattern provided by any commercially available lighting apparatus is a linear pattern, a planar pattern or a grid pattern, the projected position of the structured light pattern on the surface of the object does not vary with time for fixed pattern type, i.e., without moving part. Consequently, the corresponding projection area or resolution is limited, or the projected contents of the structured light pattern are not distinguished enough for spatial information extraction or indication. Under this circumstance, the applications of the structured light pattern are restricted, and thus the structured light pattern cannot be used in the subsequent process of precisely calculating the spatial information. These issues can be solved by using moving parts such that the lighting pattern is changed and hence the spatial information is further resolved. Nevertheless, there are still some drawbacks. For example, in case that a microelectromechanical system is used to generate the structure light pattern with the assistance of a movable optical module, the power consumption is generally very high. Moreover, since the demands on the assembling tolerances of the moving parts are stringent, the production yield is low and the durability is impaired. In other words, the conventional lighting apparatus which is with or without moving parts still needs to be improved.